Late Pleistocene-Holocene earthquake-induced slumps and soft-sediment deformation structures in the Acequion River valley, Central Precordillera, Argentina

Abstract

Evidence of earthquake-induced liquefaction features in the Acequión river valley, central western Argentina, is analysed. Well-preserved soft-sediment deformation structures are present in Late Pleistocene deposits; they include two large slumps and several sand dikes, convolutions, pseudonodules, faults, dish structures and diapirs in the basal part of a shallow-lacustrine succession in the El Acequión River area. The water-saturated state of these sediments favoured deformation. All structures were studied in a natural trench created as a result of erosion by a tributary of the Acequión River, called El Mono Creek. They form part of a large-scale slump system. Two slumps occur in the western portion of the trench and must have moved towards the ENE (70°), where the depocentre of the Boca del Acequión area is situated. Considering the spatial relationship with Quaternary faults, the slumps are interpreted as being due to a seismic event. The thickest dikes in the El Mono Creek trench occur in the eastern portion of the trench, indicating that the responsible earthquake was located to the east of the study area, probably at the Cerro Salinas fault system zone. The slumps, sand dikes and other soft-sediment deformation features are interpreted as having been triggered by earthquakes, thus providing a preliminary palaeoseismic record of the Cerro Salinas fault system and extending the record of moderate-to high-magnitude earthquakes in central western Argentina to the Late Pleistocene.

SYN-SEDIMENTARY DEFORMATION STRUCTURES in the EARLY MIOCENE LACUSTRINE DEPOSITS, the BASAL LIMESTONE UNIT, BİGADİÇ BASİN (BALIKESİR, TURKEY)

“…They may also occur due to the sloping of layers related with tectonic activities (faulting etc.) (Maltman, 1994a(Maltman, , 1994bSiegenthaler et al, 1987;Mastrogiacomo et al, 2012;Perucca et al, 2014).…”

Slumping as a record of regional tectonics and palaeoslope changes in the Satpura Basin, central India

“…SSDS are generally produced by reorganisation of original particles in sediments and sedimentary rocks. Studies of such SSDS have been carried out in a wide range of geological environments, ranging from continental to coastal and marine, spanning from the Palaeoproterozoic to the present time (e.g., Allen, 1984;Maltman, 1994aMaltman, , 1994bMaltman et al, 2000;Alfaro et al,2002;Ettensohn et al, 2002;Mazumder et al, 2006Mazumder et al, , 2016Van Loon, 2009Perucca et al, 2014;Üner, 2014;Alsop et al, 2017Alsop et al, , 2019Hubert-Ferrari et al, 2017;Byun et al, 2019).…”